Automatic and accurate scrap metal sorting in recycling plants could give large savings in economy and environment. One key ingredient is fast identification of the composition of each individual metal piece.

Laser Induced Breakdown Spectroscopy (LIBS), is one method of identifying the material constituents of a sample. In LIBS, a high power laser pulse creates a plasma on the surface of the metal piece. The spectrum of the plasma is detected by a compact spectrometer and is used to identify the atomic composition of the sample.

In this project, Acreo develops a LIBS system for analyzing scrap metal in close collaboration with Swerea KIMAB. The system enables on-line monitoring at speeds up to 30 samples/s, where the sample can be placed at a distance of up to 1m from the system. Field trials of the system placed over a conveyor belt carrying have been successfully conducted during 2011 and 2012 at our parners sites.

The system is now ready to be evaluated for various applications, from metal recycling and mining to process control applications.